This invention relates to a roll for use in a belt caster and an associated method and more particularly to a roll having a plurality of segments that are adapted to move in order to compensate for distortions in the belt.
Belt casters are well known to those skilled in the art. More particularly, twin belt casters are used to continuously cast metal products directly from molten metal in a casting region or solidification zone defined between spaced portions of a pair of revolving, flexible casting belts which are moved along with the metal being cast. Such casters can be oriented in a generally horizontal or generally vertical direction or can be angularly disposed. See, generally, U.S. Pat. No. 4,552,201 and other patents cited therein (horizontal twin belt casters) and U.S. Pat. No. 4,964,456 (vertical twin belt caster).
In order to continuously cast the molten metal into a metal product, it is critical that the belts remain substantially flat in the solidification zone. Non-planar belts create non-uniform transverse contact with the solidifying slab thus in turn causing degradation in slab quality. This degradation in slab quality causes further belt distortion itself. Thus, it can be seen that once the belt becomes non-planar, slab quality is difficult, if not impossible to maintain.
There have been several solutions proposed for the non-planar belt problem. U.S. Pat. No. 4,552,201 provides a belt-support system including back-up rollers which shape and maintain the casting region. U.S. Pat. No. 4,964,456 discloses stretching the belt past its elastic limit whereby the belt is strained to the extent that a contraction of its cross-sectional area takes place to counteract its thermal expansion, thus resisting buckling. Finally, others have suggested pretreating the belt surface (U.S. Pat. No. 3,871,905) or preheating the belts prior to their entering into the solidification zone (U.S. Pat. Nos. 4,002,197 and 4,537,243).
There are various problems and shortcomings associated with each of these prior art solutions. Thus, there remains a need for an apparatus that facilitates maintaining the belt in a twin belt caster in a planar position in the solidification zone.